HR: 09:30h
AN: V41B-07    [PDF]
TI: Density Measurement of Silicate Glass by In Situ X-ray Absorption Method
AU: * Urakawa, S
EM: urakawa@cc.okayama-u.ac.jp
AF: Department of Earth Sciences, Okayama University, 3-1-1 Tsushima naka, Okayama, 7008530 Japan
AU: Ando, R
EM: andou_rt@ganko.tohoku.ac.jp
AF: Institute of Mineralogy, Petrology and Economic Geology, Tohoku University, Aoba-ku, Sendai, 9808577 Japan
AU: Ohtani, E
EM: ohtani@mail.cc.tohoku.ac.jp
AF: Institute of Mineralogy, Petrology and Economic Geology, Tohoku University, Aoba-ku, Sendai, 9808577 Japan
AU: Katayama, Y
EM: katayama@spring8.or.jp
AF: Synchrotron Radiation Research Center, Japan Atomic Energy Research Institute, 1-1-1 Koto, Mikaduki, 6795148 Japan
AB: Density is an important physical property to understand high-pressure behaviors of silicate glass and melt. There, however, have not been adequate methods to determine the density of silicate glass and melt at high pressures and high temperatures. We applied x-ray absorption method to silicate glass with low x-ray absorption coefficient, by using a diamond sample container. We measured the densities of basalt composition glass and Fe-bearing sodium silicate glass up to 5 GPa and 773K using synchrotron radiation. High-pressure x-ray absorption experiments were conducted at BL22XU in SPring-8, where the cubic type multianvil press, SMAP180 is installed and a monochromatic x-ray is available. To detect the absorption contrast between silicate and surrounding materials, we used a single crystal diamond ring as a sample container and a boron-epoxy resin as a pressure-transmitting medium. Intensities of incident and transmitted x-ray were measured by ion chambers, in which we used the monochromatic x-ray with 25.13 keV. We can evaluate the density of glass from the x-ray absorption profile along a radial direction of a cylindrical sample, because deformation of diamond ring is very small in this pressure range and x-ray absorption of diamond is lower than silicate. We observed 20-30 % increase of densities of basalt composition glass and Fe-bearing sodium silicate glass along room temperature compression from 0.1 MPa to 5 GPa, and also detected density increase in both silicate glasses with increasing temperature at high-pressure by structural relaxation.
DE: 3919 Equations of state
DE: 3924 High-pressure behavior
DE: 3954 X ray, neutron, and electron spectroscopy and diffraction
DE: 3994 Instruments and techniques
DE: 8439 Physics and chemistry of magma bodies
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting